As the Internet adds valuable new domain names that are luring the likes of Google and Amazon, a little-known company called Donuts Inc. is making a grab that opponents say could fuel cybersquatting, the practice of stealing website identities.

Donuts, backed by more than $100 million in venture capital, is spending $56 million to bid for 307 of the 1,400 new so-called generic top-level domain names, or TLDs, that will shape how the Web will soon evolve. Instead of .com, the new names include suffixes such as .book, .app and .law.

A lawyer who represents holders of top-level domain name is seeking to thwart Donuts' efforts and is asking the Internet Corporation for Assigned Names and Numbers, which authorizes domain name suffixes and is known as Icann, to investigate Donuts' links to Demand Media Inc. That company's clients have used domain names to masquerade as other businesses, the lawyer contends. The chief executive officer of Donuts came from Demand Media, and Donuts has an arrangement to sell Demand Media 107 of its domain names if it chooses to release them.

"Donuts and its key executives are, by Icann's established eligibility guidelines, unsuited and ineligible to participate," the attorney, Jeffrey Stoler, wrote in a July letter to Icann, which manages the architecture of the Web. "Icann can and should reject the applications from Donuts and its subsidiaries, Demand Media and its subsidiaries, and their respective affiliated companies."

Donuts of Bellevue, Wash., and Demand Media are distinct companies with no equity relationship, and Donuts is "100 percent qualified" to be a registry of top-level domain names, said Brian Jacobs, founder and general partner of San Mateo's Emergence Capital Partners, a Donuts backer.

The company is bidding for so many top-level names because domain-name expansion is long overdue, said Jonathon Nevett, one of Donuts' four founders.

"When you do something bold and large, sometimes you put a target on your back," he said. "We're going to run a clean, safe registry."

Icann is now reviewing 1,930 applications for new top-level domain names in its first major expansion of Internet naming since 2004. It's an effort to eliminate the constraints companies face when trying to create a unique online name as Web browsing proliferates on smartphones and electronic tablets.

Donuts wants to build a "shopping mall" of domain names that offer breadth and depth to consumers, Nevett said.

"This has been the most constrained space you can think of," with only 22 suffixes currently available, he said. "If you think of it in the real estate market, it would be like not creating homes for years and years and years."

Though dwarfed by Google, which is seeking to own and operate the .buy and .ads domains among others, Donuts' 307 bids outnumber the search-engine giant's 99 bids. Amazon is seeking 76. Each application costs $185,000.